Somehow, the default role 'subscriber’ was removed and set as administrator.
There were hundreds of fake admin accounts in kevinellerton.com and a few in meditationuniversity.us
To fix this -
Ved set the default role as subscriber using plugin "User Role Editor"
Setting -
"User Role Editor" -> default Roles -> Primary default role : subscribers
Pages from where users get register in system -
/wp-login.php?action=register
/affiliate-area/
/affiliate-register/